The interface of transcription and DNA replication in the mitochondria

Biochim Biophys Acta. 2012 Sep-Oct;1819(9-10):970-8. doi: 10.1016/j.bbagrm.2011.12.005. Epub 2011 Dec 20.


DNA replication of the mitochondrial genome is unique in that replication is not primed by RNA derived from dedicated primases, but instead by extension of processed RNA transcripts laid down by the mitochondrial RNA polymerase. Thus, the RNA polymerase serves not only to generate the transcripts but also the primers needed for mitochondrial DNA replication. The interface between this transcription and DNA replication is not well understood but must be highly regulated and coordinated to carry out both mitochondrial DNA replication and transcription. This review focuses on the extension of RNA primers for DNA replication by the replication machinery and summarizes the current models of DNA replication in mitochondria as well as the proteins involved in mitochondrial DNA replication, namely, the DNA polymerase γ and its accessory subunit, the mitochondrial DNA helicase, the single-stranded DNA binding protein, topoisomerase I and IIIα and RNaseH1. This article is part of a Special Issue entitled: Mitochondrial Gene Expression.

Publication types

  • Research Support, N.I.H., Intramural
  • Review

MeSH terms

  • DNA Helicases / genetics
  • DNA Helicases / metabolism
  • DNA Polymerase gamma
  • DNA Replication / genetics*
  • DNA Topoisomerases / genetics
  • DNA Topoisomerases / metabolism
  • DNA, Mitochondrial / genetics*
  • DNA-Directed DNA Polymerase* / genetics
  • DNA-Directed DNA Polymerase* / metabolism
  • DNA-Directed RNA Polymerases* / genetics
  • Humans
  • Mitochondria* / enzymology
  • Mitochondria* / genetics
  • RNA / genetics
  • Transcription, Genetic


  • DNA, Mitochondrial
  • RNA primers
  • RNA
  • DNA-Directed RNA Polymerases
  • DNA Polymerase gamma
  • DNA-Directed DNA Polymerase
  • DNA Helicases
  • DNA Topoisomerases